Wireless transceiver systems are used in a variety of consumer electronics, medical devices, automotive electronics, industrial applications and other applications where reduced form factor and reduced cost are driving motivations. Of course, regardless of the application, a high signal-to-noise (SNR) ratio is desired, which requires a high fundamental signal to harmonic ratio.
To communicate over long distances, a high-output power amplifier is required. In certain applications, a transceiver will not meet Federal Communications Commission (FCC) requirements (e.g., spectral mask requirements) if there is too much harmonic content in the output wave form. Conventionally, in order to achieve sufficient harmonic reduction, significant filtering is applied using either on-chip or off-chip components, which require calibration and trimming, and consume area and power. In particular, in high-volume applications, such external filtering components are highly undesirable due to their contribution to cost and power consumption.